The last avalanche forecast for the 2023-2024 season will post on April 21st. Thank you to all who contributed to the avalanche center this season through observations, volunteer time, and/or financial contributions.

Sensitive wind slabs on Powderhouse

Location Name: Powderhouse Region: Luther Pass Area (including Job and Freel) Observation Date & Time: Wednesday, March 25, 2020 - 09:00
Location: 38.782750, -119.979791 See map: CalTopo	Is this an Avalanche Observation?: Yes Conditions Alerts: Avalanche Activity Other Signs of Instability (cracking, whumpfing, collapsing) Other Signs of Instability (cracking, whumpfing, collapsing)›Shooting Cracks Recent Loading Recent Loading›Blowing Snow Recent Loading›More Than a Foot of New Snow Recent Loading›Snowfall Rates of More Than 1 in/hr Terrain Alerts: Slopes Steeper than 30 degrees Trigger Points Terrain Traps Terrain Matches the Advisory

Location Name:

Powderhouse

Region:

Luther Pass Area (including Job and Freel)

Observation Date & Time:

Wednesday, March 25, 2020 - 09:00

Location:

38.782750, -119.979791

See map: CalTopo

Is this an Avalanche Observation?:

Yes

Conditions Alerts:

Avalanche Activity
Other Signs of Instability (cracking, whumpfing, collapsing)
Other Signs of Instability (cracking, whumpfing, collapsing)›Shooting Cracks
Recent Loading
Recent Loading›Blowing Snow
Recent Loading›More Than a Foot of New Snow
Recent Loading›Snowfall Rates of More Than 1 in/hr

Terrain Alerts:

Slopes Steeper than 30 degrees

Trigger Points

Terrain Traps

Terrain Matches the Advisory

Observation made by: Public

Tabs

Observation

Description of Snow, Weather, and Avalanche Conditions:

We found 6-12" of cold unconsolidated snow in below treeline terrain. Loose dry sluffs were common on steeper terrain. No obvious storm slab.
On the ridgeline found 8-12" deep, very sensitive wind slabs that we could easily trigger. They didn't extend far down the slope but could easily take out the feet of a skier with trees below.

Snowpack Details

Persistent Weak Layers:

Not observed

Avalanche Details

Avalanche Type:

Wind Slab

Failure Plane/Weak Layer:

New/old snow interface

Trigger

Trigger:

Skier

Trigger Modifier:

Intentionally Triggered

Terrain

Start Zone Slope Angle:

37degrees

Aspect:

North

Starting Elevation:

near-treeline

Size

Destructive Size:

D1 Relatively harmless to people.

Relative Size:

R1 Very Small

Crown Height:

1 ft

Avalanche Width (Average width):

15ft.

Avalanche Length (Vertical Run):

25ft.

People Involved

Number of people caught:

Weather Details

Elevation of Observation:

8000 - 9000 ft.

Blowing Snow:

Moderate

Wind Direction:

Southwest

Wind Speed:

Moderate

Sky Cover:

Broken - Mostly Cloudy - more than 4/8 and less than 8/8

Highest Precipitation Rate:

Very Light Snowfall (S-1 = up to .5cm /~.25 in per hour)

Precipitation:

Snow

Air temperature:

Below Freezing

Sponsors:

This website is owned and maintained by the non-profit arm of the Sierra Avalanche Center. Some of the content is updated by the USDA avalanche forecasters including the forecasts and some observational data. The USDA is not responsible for any advertising, fund-raising events/information, or sponsorship information, or other content not related to the forecasts and the data pertaining to the forecasts.

Forecast Links

Subscriptions

Forecast Tutorials

Observations

Incidents

Submit Observations

Subscriptions

Remote Weather Stations

National Weather Service

Model Forecasts

Local Resources

The SAC Daily Flow

Forecast Tutorials

Other Resources

Sensitive wind slabs on Powderhouse

Conditions Alerts:

Tabs

Sponsors:

Forecast Links

Subscriptions

Forecast Tutorials

Observations

Incidents

Submit Observations

Subscriptions

Remote Weather Stations

National Weather Service

Model Forecasts

Local Resources

The SAC Daily Flow

Forecast Tutorials

Other Resources

Sensitive wind slabs on Powderhouse

Conditions Alerts:

Tabs

Search form

Follow Us

Sponsors: